From ca315724ff09597cd938314fa9b1a3a4d6dfdb3a Mon Sep 17 00:00:00 2001
From: Gwenhael Le Moine <gwenhael.le.moine@gmail.com>
Date: Wed, 10 Nov 2021 11:01:26 +0100
Subject: [PATCH] add runner and dictionary

---
 lib/dictionary.rb   | 24 ++++++++++++++++++++++++
 lib/parser.rb       | 10 +---------
 lib/runner.rb       | 26 ++++++++++++++++++++++++++
 repl.rb             | 37 +++++++++++++------------------------
 spec/parser_spec.rb |  9 ++++++++-
 5 files changed, 72 insertions(+), 34 deletions(-)
 create mode 100644 lib/dictionary.rb
 create mode 100644 lib/runner.rb

diff --git a/lib/dictionary.rb b/lib/dictionary.rb
new file mode 100644
index 0000000..85eed64
--- /dev/null
+++ b/lib/dictionary.rb
@@ -0,0 +1,24 @@
+# coding: utf-8
+
+module Rpn
+  class Dictionary
+    def initialize
+      @parser = Parser.new
+      @words = {
+        '+' => proc { |stack|
+          stack + @parser.parse_input( (stack.pop[:value] + stack.pop[:value]).to_s )
+        },
+      }
+    end
+
+    def add( word )
+      @words[ word[:name] ] = word[:value]
+    end
+
+    def lookup( name )
+      @words[ name ] if @words.include?( name )
+    end
+
+    # TODO: alias
+  end
+end
diff --git a/lib/parser.rb b/lib/parser.rb
index c3242e2..a328899 100644
--- a/lib/parser.rb
+++ b/lib/parser.rb
@@ -19,6 +19,7 @@ module Rpn
       closed_programs = 0
       string_delimiters = 0
       regrouping = false
+
       regrouped_input = []
       splitted_input.each do |elt|
         # TODO: handle buried-in-elt « and » (surround by ' ' and re-split)
@@ -64,15 +65,6 @@ module Rpn
                                 end
                               end
 
-        if parsed_entry[:type] == :word
-          if false
-          # TODO: run word if known
-          else
-            parsed_entry[:type] = :name
-            parsed_entry[:value] = "'#{parsed_entry[:value]}'" if parsed_entry[:value][0] != "'"
-          end
-        end
-
         if parsed_entry[:type] == :numeric
           i = parsed_entry[:value].to_i
           f = parsed_entry[:value].to_f
diff --git a/lib/runner.rb b/lib/runner.rb
new file mode 100644
index 0000000..710437c
--- /dev/null
+++ b/lib/runner.rb
@@ -0,0 +1,26 @@
+# coding: utf-8
+
+module Rpn
+  class Runner
+    def initialize; end
+
+    def run_input( stack, dictionary, input )
+      input.each do |elt|
+        case elt[:type]
+        when :word
+          command = dictionary.lookup( elt[:value] )
+
+          if command.nil?
+            stack << { type: :name, value: "'#{elt[:value]}'" }
+          else
+            stack = command.call( stack )
+          end
+        else
+          stack << elt
+        end
+      end
+
+      [stack, dictionary]
+    end
+  end
+end
diff --git a/repl.rb b/repl.rb
index 8040d88..bf1878e 100644
--- a/repl.rb
+++ b/repl.rb
@@ -1,15 +1,19 @@
 # coding: utf-8
 # frozen_string_literal: true
 
-require "readline"
+require 'readline'
 
-require "./lib/parser.rb"
+require './lib/dictionary'
+require './lib/parser'
+require './lib/runner'
 
 module Rpn
   class Repl
     def initialize
-      @parser = Parser.new
       @stack = []
+      @dictionary = Dictionary.new
+      @parser = Parser.new
+      @runner = Runner.new
     end
 
     def run
@@ -21,39 +25,24 @@ module Rpn
           Readline::HISTORY.grep(/^#{Regexp.escape(s)}/)
         end
       end
-      Readline.completion_append_character = " "
+      Readline.completion_append_character = ' '
 
       loop do
-        input = Readline.readline( " ", true )
-        break if input.nil? || input == "exit"
+        input = Readline.readline( ' ', true )
+        break if input.nil? || input == 'exit'
 
         # Remove blank lines from history
         Readline::HISTORY.pop if input.empty?
 
-        process_input( input )
+        @stack, @dictionary = @runner.run_input( @stack, @dictionary,
+                                                 @parser.parse_input( input ) )
 
         print_stack
       end
     end
 
-    def process_input( input )
-      @parser.parse_input( input ).each do |elt|
-        @stack << elt           # TODO: (parse and) evaluate elt if needed
-      end
-    end
-
     def format_element( elt )
-      pp elt
-      # case elt[:type]
-      # when :program
-      #   "« #{elt[:value]} »"
-      # when :string
-      #   "\"#{elt[:value]}\""
-      # when :name
-      #   "'#{elt[:value]}'"
-      # else
-        elt[:value]
-      # end
+      elt[:value]
     end
 
     def print_stack
diff --git a/spec/parser_spec.rb b/spec/parser_spec.rb
index abd48a9..30420aa 100644
--- a/spec/parser_spec.rb
+++ b/spec/parser_spec.rb
@@ -13,7 +13,7 @@ class TestParser < Test::Unit::TestCase
 
   def test_word
     result = Rpn::Parser.new.parse_input( 'dup' )
-    assert_equal [{ value: "'dup'", type: :name }], result
+    assert_equal [{ value: 'dup', type: :word }], result
   end
 
   def test_string
@@ -63,6 +63,13 @@ class TestParser < Test::Unit::TestCase
     assert_equal [{ value: 2, type: :numeric }, { value: 3, type: :numeric }], result
   end
 
+  def test_number_number_word
+    result = Rpn::Parser.new.parse_input( '2 3 +' )
+    assert_equal [{ value: 2, type: :numeric },
+                  { value: 3, type: :numeric },
+                  { value: '+', type: :word }], result
+  end
+
   def test_number_string
     result = Rpn::Parser.new.parse_input( '4 "test"' )
     assert_equal [{ value: 4, type: :numeric }, { value: '"test"', type: :string }], result